diff --git a/webapp/components/add_users_to_team/add_users_to_team.jsx b/webapp/components/add_users_to_team/add_users_to_team.jsx
index ae6fd8c4e1..ee22bbed58 100644
--- a/webapp/components/add_users_to_team/add_users_to_team.jsx
+++ b/webapp/components/add_users_to_team/add_users_to_team.jsx
@@ -2,7 +2,7 @@
 // See License.txt for license information.
 
 import MultiSelect from 'components/multiselect/multiselect.jsx';
-import ProfilePicture from 'components/profile_picture.jsx';
+import ProfilePicture from 'components/profile_popover/picture_profile_popover.jsx';
 
 import {addUsersToTeam} from 'actions/team_actions.jsx';
 import {searchUsersNotInTeam} from 'actions/user_actions.jsx';
diff --git a/webapp/components/more_direct_channels/more_direct_channels.jsx b/webapp/components/more_direct_channels/more_direct_channels.jsx
index 50e2c4e485..743236ce61 100644
--- a/webapp/components/more_direct_channels/more_direct_channels.jsx
+++ b/webapp/components/more_direct_channels/more_direct_channels.jsx
@@ -2,7 +2,7 @@
 // See License.txt for license information.
 
 import MultiSelect from 'components/multiselect/multiselect.jsx';
-import ProfilePicture from 'components/profile_picture.jsx';
+import ProfilePicture from 'components/profile_popover/picture_profile_popover.jsx';
 
 import {searchUsers} from 'actions/user_actions.jsx';
 import {openDirectChannelToUser, openGroupChannelToUsers} from 'actions/channel_actions.jsx';
diff --git a/webapp/components/popover_list_members/popover_list_members.jsx b/webapp/components/popover_list_members/popover_list_members.jsx
index cf6042943d..458ae8f247 100644
--- a/webapp/components/popover_list_members/popover_list_members.jsx
+++ b/webapp/components/popover_list_members/popover_list_members.jsx
@@ -1,7 +1,7 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See License.txt for license information.
 
-import ProfilePicture from 'components/profile_picture.jsx';
+import ProfilePicture from 'components/profile_popover/picture_profile_popover.jsx';
 
 import TeamStore from 'stores/team_store.jsx';
 import UserStore from 'stores/user_store.jsx';
diff --git a/webapp/components/post_view/components/post.jsx b/webapp/components/post_view/components/post.jsx
index f5c96d2bc7..cf25b28e4f 100644
--- a/webapp/components/post_view/components/post.jsx
+++ b/webapp/components/post_view/components/post.jsx
@@ -3,7 +3,7 @@
 
 import PostHeader from './post_header.jsx';
 import PostBody from './post_body.jsx';
-import ProfilePicture from 'components/profile_picture.jsx';
+import ProfilePicture from 'components/profile_popover/picture_profile_popover.jsx';
 
 import Constants from 'utils/constants.jsx';
 const ActionTypes = Constants.ActionTypes;
diff --git a/webapp/components/post_view/components/post_header.jsx b/webapp/components/post_view/components/post_header.jsx
index 9de0b7e798..e19285963d 100644
--- a/webapp/components/post_view/components/post_header.jsx
+++ b/webapp/components/post_view/components/post_header.jsx
@@ -1,7 +1,7 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See License.txt for license information.
 
-import UserProfile from 'components/user_profile.jsx';
+import UserProfile from 'components/profile_popover/username_profile_popover.jsx';
 import PostInfo from './post_info.jsx';
 import {FormattedMessage} from 'react-intl';
 
diff --git a/webapp/components/post_view/components/post_message_view.jsx b/webapp/components/post_view/components/post_message_view.jsx
index 5b0790f36c..db522c974a 100644
--- a/webapp/components/post_view/components/post_message_view.jsx
+++ b/webapp/components/post_view/components/post_message_view.jsx
@@ -3,6 +3,9 @@
 
 import React from 'react';
 import {FormattedMessage} from 'react-intl';
+import {Parser, ProcessNodeDefinitions} from 'html-to-react';
+
+import AtMentionProfile from 'components/profile_popover/atmention_profile_popover.jsx';
 
 import Constants from 'utils/constants.jsx';
 import * as PostUtils from 'utils/post_utils.jsx';
@@ -88,6 +91,38 @@ export default class PostMessageView extends React.Component {
         );
     }
 
+    postMessageHtmlToComponent(html) {
+        const parser = new Parser();
+        const attrib = 'data-mention';
+        const processNodeDefinitions = new ProcessNodeDefinitions(React);
+
+        function isValidNode() {
+            return true;
+        }
+
+        const processingInstructions = [
+            {
+                replaceChildren: true,
+                shouldProcessNode: (node) => node.attribs && node.attribs[attrib] && this.props.usernameMap.hasOwnProperty(node.attribs[attrib]),
+                processNode: (node) => {
+                    const username = node.attribs[attrib];
+                    return (
+                        <AtMentionProfile
+                            user={this.props.usernameMap[username]}
+                            username={username}
+                        />
+                    );
+                }
+            },
+            {
+                shouldProcessNode: () => true,
+                processNode: processNodeDefinitions.processDefaultNode
+            }
+        ];
+
+        return parser.parseWithInstructions(html, isValidNode, processingInstructions);
+    }
+
     render() {
         if (this.props.post.state === Constants.POST_DELETED) {
             return this.renderDeletedPost();
@@ -111,14 +146,17 @@ export default class PostMessageView extends React.Component {
             return <div>{renderedSystemMessage}</div>;
         }
 
+        const htmlFormattedText = TextFormatting.formatText(this.props.post.message, options);
+        const postMessageComponent = this.postMessageHtmlToComponent(htmlFormattedText);
+
         return (
             <div>
                 <span
                     id={this.props.isLastPost ? 'lastPostMessageText' : null}
                     className='post-message__text'
                     onClick={Utils.handleFormattedTextClick}
-                    dangerouslySetInnerHTML={{__html: TextFormatting.formatText(this.props.post.message, options)}}
                 />
+                {postMessageComponent}
                 {this.renderEditedIndicator()}
             </div>
         );
diff --git a/webapp/components/profile_popover/atmention_profile_popover.jsx b/webapp/components/profile_popover/atmention_profile_popover.jsx
new file mode 100644
index 0000000000..47c625f64d
--- /dev/null
+++ b/webapp/components/profile_popover/atmention_profile_popover.jsx
@@ -0,0 +1,95 @@
+// Copyright (c) 2017-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+import ProfilePopover from './profile_popover.jsx';
+import * as Utils from 'utils/utils.jsx';
+import Client from 'client/web_client.jsx';
+
+import {OverlayTrigger} from 'react-bootstrap';
+
+import React from 'react';
+
+export default class AtMentionProfile extends React.Component {
+    constructor(props) {
+        super(props);
+
+        this.hideProfilePopover = this.hideProfilePopover.bind(this);
+    }
+
+    shouldComponentUpdate(nextProps) {
+        if (!Utils.areObjectsEqual(nextProps.user, this.props.user)) {
+            return true;
+        }
+
+        if (nextProps.overwriteImage !== this.props.overwriteImage) {
+            return true;
+        }
+
+        if (nextProps.disablePopover !== this.props.disablePopover) {
+            return true;
+        }
+
+        if (nextProps.displayNameType !== this.props.displayNameType) {
+            return true;
+        }
+
+        if (nextProps.status !== this.props.status) {
+            return true;
+        }
+
+        if (nextProps.isBusy !== this.props.isBusy) {
+            return true;
+        }
+
+        return false;
+    }
+
+    hideProfilePopover() {
+        this.refs.overlay.hide();
+    }
+
+    render() {
+        let profileImg = '';
+        if (this.props.user) {
+            profileImg = Client.getUsersRoute() + '/' + this.props.user.id + '/image?time=' + this.props.user.last_picture_update;
+        }
+
+        if (this.props.disablePopover) {
+            return <a className='mention-link'>{'@' + this.props.username}</a>;
+        }
+
+        return (
+            <OverlayTrigger
+                ref='overlay'
+                trigger='click'
+                placement='right'
+                rootClose={true}
+                overlay={
+                    <ProfilePopover
+                        user={this.props.user}
+                        src={profileImg}
+                        status={this.props.status}
+                        isBusy={this.props.isBusy}
+                        hide={this.hideProfilePopover}
+                    />
+                }
+            >
+                <a className='mention-link'>{'@' + this.props.username}</a>
+            </OverlayTrigger>
+        );
+    }
+}
+
+AtMentionProfile.defaultProps = {
+    overwriteImage: '',
+    disablePopover: false
+};
+AtMentionProfile.propTypes = {
+    user: React.PropTypes.object.isRequired,
+    username: React.PropTypes.string.isRequired,
+    overwriteImage: React.PropTypes.string,
+    disablePopover: React.PropTypes.bool,
+    displayNameType: React.PropTypes.string,
+    status: React.PropTypes.string,
+    isBusy: React.PropTypes.bool
+};
diff --git a/webapp/components/profile_picture.jsx b/webapp/components/profile_popover/picture_profile_popover.jsx
similarity index 98%
rename from webapp/components/profile_picture.jsx
rename to webapp/components/profile_popover/picture_profile_popover.jsx
index b7ee087851..2c2b91b25c 100644
--- a/webapp/components/profile_picture.jsx
+++ b/webapp/components/profile_popover/picture_profile_popover.jsx
@@ -1,10 +1,11 @@
 // Copyright (c) 2016-present Mattermost, Inc. All Rights Reserved.
 // See License.txt for license information.
+
 import ProfilePopover from './profile_popover.jsx';
 import * as Utils from 'utils/utils.jsx';
 
 import React from 'react';
-import StatusIcon from './status_icon.jsx';
+import StatusIcon from 'components/status_icon.jsx';
 import {OverlayTrigger} from 'react-bootstrap';
 
 export default class ProfilePicture extends React.Component {
diff --git a/webapp/components/profile_popover.jsx b/webapp/components/profile_popover/profile_popover.jsx
similarity index 82%
rename from webapp/components/profile_popover.jsx
rename to webapp/components/profile_popover/profile_popover.jsx
index 63bd99ac4c..a32b7904b6 100644
--- a/webapp/components/profile_popover.jsx
+++ b/webapp/components/profile_popover/profile_popover.jsx
@@ -23,11 +23,19 @@ export default class ProfilePopover extends React.Component {
 
         this.initWebrtc = this.initWebrtc.bind(this);
         this.handleShowDirectChannel = this.handleShowDirectChannel.bind(this);
+        this.generateImage = this.generateImage.bind(this);
+        this.generateFullname = this.generateFullname.bind(this);
+        this.generatePosition = this.generatePosition.bind(this);
+        this.generateWebrtc = this.generateWebrtc.bind(this);
+        this.generateEmail = this.generateEmail.bind(this);
+        this.generateDirectMessage = this.generateDirectMessage.bind(this);
+
         this.state = {
             currentUserId: UserStore.getCurrentId(),
             loadingDMChannel: -1
         };
     }
+
     shouldComponentUpdate(nextProps) {
         if (!Utils.areObjectsEqual(nextProps.user, this.props.user)) {
             return true;
@@ -102,19 +110,63 @@ export default class ProfilePopover extends React.Component {
         }
     }
 
-    render() {
-        const popoverProps = Object.assign({}, this.props);
-        delete popoverProps.user;
-        delete popoverProps.src;
-        delete popoverProps.status;
-        delete popoverProps.isBusy;
-        delete popoverProps.hide;
+    generateImage(src) {
+        return (
+            <img
+                className='user-popover__image'
+                src={src}
+                height='128'
+                width='128'
+                key='user-popover-image'
+            />
+        );
+    }
 
-        let webrtc;
+    generateFullname() {
+        const fullname = Utils.getFullName(this.props.user);
+        if (fullname) {
+            return (
+                <OverlayTrigger
+                    delayShow={Constants.WEBRTC_TIME_DELAY}
+                    placement='top'
+                    overlay={<Tooltip id='fullNameTooltip'>{fullname}</Tooltip>}
+                >
+                    <div
+                        className='overflow--ellipsis text-nowrap padding-bottom'
+                    >
+                        {fullname}
+                    </div>
+                </OverlayTrigger>
+            );
+        }
+
+        return '';
+    }
+
+    generatePosition() {
+        if (this.props.user.hasOwnProperty('position')) {
+            const position = this.props.user.position.substring(0, Constants.MAX_POSITION_LENGTH);
+            return (
+                <OverlayTrigger
+                    delayShow={Constants.WEBRTC_TIME_DELAY}
+                    placement='top'
+                    overlay={<Tooltip id='positionTooltip'>{position}</Tooltip>}
+                >
+                    <div
+                        className='overflow--ellipsis text-nowrap padding-bottom'
+                    >
+                        {position}
+                    </div>
+                </OverlayTrigger>
+            );
+        }
+
+        return '';
+    }
+
+    generateWebrtc() {
         const userMedia = navigator.getUserMedia || navigator.webkitGetUserMedia || navigator.mozGetUserMedia;
-
         const webrtcEnabled = global.mm_config.EnableWebrtc === 'true' && userMedia && Utils.isFeatureEnabled(PreReleaseFeatures.WEBRTC_PREVIEW);
-
         if (webrtcEnabled && this.props.user.id !== this.state.currentUserId) {
             const isOnline = this.props.status !== UserStatuses.OFFLINE;
             let webrtcMessage;
@@ -141,7 +193,7 @@ export default class ProfilePopover extends React.Component {
                 );
             }
 
-            webrtc = (
+            return (
                 <div
                     data-toggle='tooltip'
                     key='makeCall'
@@ -160,54 +212,15 @@ export default class ProfilePopover extends React.Component {
             );
         }
 
-        var dataContent = [];
-        dataContent.push(
-            <img
-                className='user-popover__image'
-                src={this.props.src}
-                height='128'
-                width='128'
-                key='user-popover-image'
-            />
-        );
+        return '';
+    }
 
-        const fullname = Utils.getFullName(this.props.user);
-        if (fullname) {
-            dataContent.push(
-                <OverlayTrigger
-                    delayShow={Constants.WEBRTC_TIME_DELAY}
-                    placement='top'
-                    overlay={<Tooltip id='fullNameTooltip'>{fullname}</Tooltip>}
-                >
-                    <div
-                        className='overflow--ellipsis text-nowrap padding-bottom'
-                    >
-                        {fullname}
-                    </div>
-                </OverlayTrigger>
-            );
-        }
+    generateEmail() {
+        const email = this.props.user.hasOwnProperty('email') ? this.props.user.email : '';
+        const showEmail = (global.window.mm_config.ShowEmailAddress === 'true' || UserStore.isSystemAdminForCurrentUser() || this.props.user === UserStore.getCurrentUser());
 
-        if (this.props.user.position) {
-            const position = this.props.user.position.substring(0, Constants.MAX_POSITION_LENGTH);
-            dataContent.push(
-                <OverlayTrigger
-                    delayShow={Constants.WEBRTC_TIME_DELAY}
-                    placement='top'
-                    overlay={<Tooltip id='positionTooltip'>{position}</Tooltip>}
-                >
-                    <div
-                        className='overflow--ellipsis text-nowrap padding-bottom'
-                    >
-                        {position}
-                    </div>
-                </OverlayTrigger>
-            );
-        }
-
-        const email = this.props.user.email;
-        if (global.window.mm_config.ShowEmailAddress === 'true' || UserStore.isSystemAdminForCurrentUser() || this.props.user === UserStore.getCurrentUser()) {
-            dataContent.push(
+        if (email !== '' && showEmail) {
+            return (
                 <div
                     data-toggle='tooltip'
                     title={email}
@@ -223,8 +236,12 @@ export default class ProfilePopover extends React.Component {
             );
         }
 
+        return '';
+    }
+
+    generateDirectMessage() {
         if (this.props.user.id !== UserStore.getCurrentId()) {
-            dataContent.push(
+            return (
                 <div
                     data-toggle='tooltip'
                     key='user-popover-dm'
@@ -243,16 +260,27 @@ export default class ProfilePopover extends React.Component {
                     </a>
                 </div>
             );
-            dataContent.push(webrtc);
         }
 
+        return '';
+    }
+
+    render() {
         return (
             <Popover
-                {...popoverProps}
+                arrowOffsetLeft={this.props.arrowOffsetLeft}
+                arrowOffsetTop={this.props.arrowOffsetTop}
+                positionLeft={this.props.positionLeft}
+                positionTop={this.props.positionTop}
                 title={'@' + this.props.user.username}
                 id='user-profile-popover'
             >
-                {dataContent}
+                {this.generateImage(this.props.src)}
+                {this.generateFullname()}
+                {this.generatePosition()}
+                {this.generateEmail()}
+                {this.generateDirectMessage()}
+                {this.generateWebrtc()}
             </Popover>
         );
     }
diff --git a/webapp/components/user_profile.jsx b/webapp/components/profile_popover/username_profile_popover.jsx
similarity index 100%
rename from webapp/components/user_profile.jsx
rename to webapp/components/profile_popover/username_profile_popover.jsx
diff --git a/webapp/components/rhs_comment.jsx b/webapp/components/rhs_comment.jsx
index 10cd5fb555..d7b899b338 100644
--- a/webapp/components/rhs_comment.jsx
+++ b/webapp/components/rhs_comment.jsx
@@ -1,11 +1,11 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See License.txt for license information.
 
-import UserProfile from './user_profile.jsx';
+import UserProfile from './profile_popover/username_profile_popover.jsx';
 import FileAttachmentListContainer from './file_attachment_list_container.jsx';
 import PendingPostOptions from 'components/post_view/components/pending_post_options.jsx';
 import PostMessageContainer from 'components/post_view/components/post_message_container.jsx';
-import ProfilePicture from 'components/profile_picture.jsx';
+import ProfilePicture from 'components/profile_popover/picture_profile_popover.jsx';
 import ReactionListContainer from 'components/post_view/components/reaction_list_container.jsx';
 import RhsDropdown from 'components/rhs_dropdown.jsx';
 
diff --git a/webapp/components/rhs_root_post.jsx b/webapp/components/rhs_root_post.jsx
index 41dd92e91f..32d03e524d 100644
--- a/webapp/components/rhs_root_post.jsx
+++ b/webapp/components/rhs_root_post.jsx
@@ -1,11 +1,11 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See License.txt for license information.
 
-import UserProfile from './user_profile.jsx';
+import UserProfile from './profile_popover/username_profile_popover.jsx';
 import PostBodyAdditionalContent from 'components/post_view/components/post_body_additional_content.jsx';
 import PostMessageContainer from 'components/post_view/components/post_message_container.jsx';
 import FileAttachmentListContainer from './file_attachment_list_container.jsx';
-import ProfilePicture from 'components/profile_picture.jsx';
+import ProfilePicture from 'components/profile_popover/picture_profile_popover.jsx';
 import ReactionListContainer from 'components/post_view/components/reaction_list_container.jsx';
 import RhsDropdown from 'components/rhs_dropdown.jsx';
 
diff --git a/webapp/components/search_results_item.jsx b/webapp/components/search_results_item.jsx
index 09ea8c427d..846840e40e 100644
--- a/webapp/components/search_results_item.jsx
+++ b/webapp/components/search_results_item.jsx
@@ -3,9 +3,9 @@
 
 import $ from 'jquery';
 import PostMessageContainer from 'components/post_view/components/post_message_container.jsx';
-import UserProfile from './user_profile.jsx';
+import UserProfile from './profile_popover/username_profile_popover.jsx';
 import FileAttachmentListContainer from './file_attachment_list_container.jsx';
-import ProfilePicture from './profile_picture.jsx';
+import ProfilePicture from './profile_popover/picture_profile_popover.jsx';
 
 import TeamStore from 'stores/team_store.jsx';
 import UserStore from 'stores/user_store.jsx';
diff --git a/webapp/components/user_list_row.jsx b/webapp/components/user_list_row.jsx
index 3a7fc5d1c8..e4e9374328 100644
--- a/webapp/components/user_list_row.jsx
+++ b/webapp/components/user_list_row.jsx
@@ -1,7 +1,7 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See License.txt for license information.
 
-import ProfilePicture from 'components/profile_picture.jsx';
+import ProfilePicture from 'components/profile_popover/picture_profile_popover.jsx';
 
 import UserStore from 'stores/user_store.jsx';
 import PreferenceStore from 'stores/preference_store.jsx';
diff --git a/webapp/package.json b/webapp/package.json
index e7203f0d6d..d3d12a1fb8 100644
--- a/webapp/package.json
+++ b/webapp/package.json
@@ -15,6 +15,7 @@
     "flux": "3.1.2",
     "font-awesome": "4.7.0",
     "highlight.js": "9.10.0",
+    "html-to-react": "1.2.7",
     "inobounce": "0.1.4",
     "intl": "1.2.5",
     "jasny-bootstrap": "3.1.3",
diff --git a/webapp/tests/utils/formatting_at_mentions.test.jsx b/webapp/tests/utils/formatting_at_mentions.test.jsx
index d64b42c3ff..51f9bef65f 100644
--- a/webapp/tests/utils/formatting_at_mentions.test.jsx
+++ b/webapp/tests/utils/formatting_at_mentions.test.jsx
@@ -50,21 +50,6 @@ describe('TextFormatting.AtMentions', function() {
         );
     });
 
-    it('Implied at mentions', function() {
-        // PLT-4454 Assume users exist for things that look like at mentions until we support the new mention syntax
-        assert.equal(
-            TextFormatting.autolinkAtMentions('@user', new Map(), {}),
-            '$MM_ATMENTION0',
-            'should imply user exists and replace mention with token'
-        );
-
-        assert.equal(
-            TextFormatting.autolinkAtMentions('@user.', new Map(), {}),
-            '$MM_ATMENTION0.',
-            'should assume username doesn\'t end in punctuation'
-        );
-    });
-
     it('Not at mentions', function() {
         assert.equal(
             TextFormatting.autolinkAtMentions('user@host', new Map(), {user: {}, host: {}}),
@@ -75,5 +60,28 @@ describe('TextFormatting.AtMentions', function() {
             TextFormatting.autolinkAtMentions('user@email.com', new Map(), {user: {}, email: {}}),
             'user@email.com'
         );
+
+        assert.equal(
+            TextFormatting.autolinkAtMentions('@user', new Map(), {}),
+            '@user'
+        );
+
+        assert.equal(
+            TextFormatting.autolinkAtMentions('@user.', new Map(), {}),
+            '@user.',
+            'should assume username doesn\'t end in punctuation'
+        );
+
+        assert.equal(
+            TextFormatting.autolinkAtMentions('@will', new Map(), {william: {}}),
+            '@will',
+            'should return same text without token'
+        );
+
+        assert.equal(
+            TextFormatting.autolinkAtMentions('@william', new Map(), {will: {}}),
+            '@william',
+            'should return same text without token'
+        );
     });
 });
diff --git a/webapp/tests/utils/formatting_hashtags.test.jsx b/webapp/tests/utils/formatting_hashtags.test.jsx
index 1740a8ce7f..0aadd66263 100644
--- a/webapp/tests/utils/formatting_hashtags.test.jsx
+++ b/webapp/tests/utils/formatting_hashtags.test.jsx
@@ -166,7 +166,7 @@ describe('TextFormatting.Hashtags', function() {
         };
         assert.equal(
             TextFormatting.formatText('#@test', options).trim(),
-            "<p>#<a class='mention-link' href='#' data-mention='test'>@test</a></p>"
+            "<p>#<span data-mention='test'><a class='mention-link' href='#'>@test</a></span></p>"
         );
 
         assert.equal(
diff --git a/webapp/utils/channel_intro_messages.jsx b/webapp/utils/channel_intro_messages.jsx
index 31ba8708da..cc50710470 100644
--- a/webapp/utils/channel_intro_messages.jsx
+++ b/webapp/utils/channel_intro_messages.jsx
@@ -5,14 +5,14 @@ import * as Utils from './utils.jsx';
 import ChannelInviteModal from 'components/channel_invite_modal';
 import EditChannelHeaderModal from 'components/edit_channel_header_modal.jsx';
 import ToggleModalButton from 'components/toggle_modal_button.jsx';
-import UserProfile from 'components/user_profile.jsx';
+import UserProfile from 'components/profile_popover/username_profile_popover.jsx';
 import ChannelStore from 'stores/channel_store.jsx';
 import UserStore from 'stores/user_store.jsx';
 import TeamStore from 'stores/team_store.jsx';
 import Constants from 'utils/constants.jsx';
 import * as GlobalActions from 'actions/global_actions.jsx';
 import Client from 'client/web_client.jsx';
-import ProfilePicture from 'components/profile_picture.jsx';
+import ProfilePicture from 'components/profile_popover/picture_profile_popover.jsx';
 
 import {showManagementOptions} from './channel_utils.jsx';
 
diff --git a/webapp/utils/text_formatting.jsx b/webapp/utils/text_formatting.jsx
index c2c71a4e1d..bd718b3636 100644
--- a/webapp/utils/text_formatting.jsx
+++ b/webapp/utils/text_formatting.jsx
@@ -166,8 +166,13 @@ export function autolinkAtMentions(text, tokens, usernameMap) {
         const index = tokens.size;
         const alias = `$MM_ATMENTION${index}`;
 
+        let tokenValue = `<span data-mention='${username}'><a class='mention-link' href='#'>${mention}</a></span>`;
+        if (Constants.SPECIAL_MENTIONS.indexOf(username) >= 0) {
+            tokenValue = mention;
+        }
+
         tokens.set(alias, {
-            value: `<a class='mention-link' href='#' data-mention='${username}'>${mention}</a>`,
+            value: tokenValue,
             originalText: mention
         });
         return alias;
@@ -181,8 +186,7 @@ export function autolinkAtMentions(text, tokens, usernameMap) {
             const truncated = usernameLower.substring(0, c);
             const suffix = usernameLower.substring(c);
 
-            // If we've found a username or run out of punctuation to trim off, render it as an at mention
-            if (mentionExists(truncated) || !punctuation.test(truncated[truncated.length - 1])) {
+            if (mentionExists(truncated) && (c === usernameLower.length || punctuation.test(usernameLower[c]))) {
                 const alias = addToken(truncated, '@' + truncated);
                 return prefix + alias + suffix;
             }
diff --git a/webapp/utils/utils.jsx b/webapp/utils/utils.jsx
index f56b9bb097..9b29c5362e 100644
--- a/webapp/utils/utils.jsx
+++ b/webapp/utils/utils.jsx
@@ -989,12 +989,16 @@ export function changeOpacity(oldColor, opacity) {
 }
 
 export function getFullName(user) {
-    if (user.first_name && user.last_name) {
-        return user.first_name + ' ' + user.last_name;
-    } else if (user.first_name) {
-        return user.first_name;
-    } else if (user.last_name) {
-        return user.last_name;
+    if (user !== null && typeof user !== 'undefined' && typeof user === 'object') {
+        const firstName = user.hasOwnProperty('first_name') ? user.first_name : '';
+        const lastName = user.hasOwnProperty('last_name') ? user.last_name : '';
+        if (firstName && lastName) {
+            return firstName + ' ' + lastName;
+        } else if (firstName) {
+            return firstName;
+        } else if (lastName) {
+            return lastName;
+        }
     }
 
     return '';